Adriany Gregor, Van de Moortele Pierre-Francois, Wiesinger Florian, Moeller Steen, Strupp John P, Andersen Peter, Snyder Carl, Zhang Xiaoliang, Chen Wei, Pruessmann Klaas P, Boesiger Peter, Vaughan Tommy, Uğurbil Kāmil
Center for Magnetic Resonance Research, Department of Radiology, School of Medicine, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Magn Reson Med. 2005 Feb;53(2):434-45. doi: 10.1002/mrm.20321.
Transceive array coils, capable of RF transmission and independent signal reception, were developed for parallel, 1H imaging applications in the human head at 7 T (300 MHz). The coils combine the advantages of high-frequency properties of transmission lines with classic MR coil design. Because of the short wavelength at the 1H frequency at 300 MHz, these coils were straightforward to build and decouple. The sensitivity profiles of individual coils were highly asymmetric, as expected at this high frequency; however, the summed images from all coils were relatively uniform over the whole brain. Data were obtained with four- and eight-channel transceive arrays built using a loop configuration and compared to arrays built from straight stripline transmission lines. With both the four- and the eight-channel arrays, parallel imaging with sensitivity encoding with high reduction numbers was feasible at 7 T in the human head. A one-dimensional reduction factor of 4 was robustly achieved with an average g value of 1.25 with the eight-channel transmit/receive coils.
收发阵列线圈能够进行射频传输和独立信号接收,是为7T(300MHz)人体头部的并行1H成像应用而开发的。这些线圈将传输线的高频特性优势与经典的磁共振线圈设计相结合。由于在300MHz的1H频率下波长较短,这些线圈易于构建和解耦。正如在这个高频下所预期的那样,单个线圈的灵敏度分布高度不对称;然而,所有线圈的叠加图像在整个大脑上相对均匀。使用环形配置构建的四通道和八通道收发阵列获取了数据,并与由直的带状线传输线构建的阵列进行了比较。使用四通道和八通道阵列,在7T人体头部进行具有高缩减因子的灵敏度编码并行成像都是可行的。使用八通道发射/接收线圈,平均g值为1.25时,稳健地实现了一维缩减因子为4。